DEVICE Device to use as a serial port (default: "/dev/modem")
BAUD Serial speed to use (default: 9600)
DATA Number of databits to use (default: 8)
PARITY Type of parity to use (default: "none")
STOP Number of stop bits to use (default: 1)
FLOW Kind of flow control to use (default: "none")
-h, --help Help report
--skip-status Skip modem status bit tests
--hide-possible Don't show all possible settings

Some systems, serial ports, and modem behave in strange ways. To test the capabilities of Perl's Device::SerialPort, this tool queries the system settings for the given DEVICE, and attempts to set up the port and send the initialization string "ATE1" to the modem, reporting the results seen.